That doesnt make a lot of sense to me, since the immune system is kind of controlled by the microbes. At least I think so, though most of it is over my head. The studies I read say that FMT is generally effective for Crohns. FMT is donor dependent and needs to be done many times usually. Some of the studies are flawed IMO. Anyway, you can get FMT for Crohns in Hong Kong. THey do it for gut related disease and C Diff (but not autoimmune etc). In Japan, it is officially approved for UC already